Cross threaded plug...I think

[Timber0472]

Ok so I think I cross threaded my front cylinder plug on my new bike. Wtf...all the other plugs went in pretty easy but were a bitch to start. The front cylinder deep one didn't want to start at all. I wiggled the plug on the end of the wrench left and right trying to get it to bite. As soon as I felt what I thought was a good bite I started gently tightening. It went in a little rough at first and then got easier but then it got tight again. I backed it out hoping it was good. The plug didn't have any metal shavings on ut but each time time I tried tightening it up it seemed to get harder.
Anyone experience this with the new m8 or did I just F $_÷\! My new motor? I cant tell if it's seated all the way but it did come to a stopping point rather quick. Like I was at the end of the threads. I pulled it out and compared the threads that looked used to one of the other plugs and they seem the same.
Any advice?

[Timber0472]

How should I fix this properly?

[Frédéric CM]

how does the old plug goes back on ? how does the thread look ?

[les]

It might be the right time to take a deep breath, step back, and consider removing the head and getting a timesert kit.  Slow rolling forward and just fixing it might minimize the stress.

[Hunter14]

I know this isn't going to help now.....But from changing thousands of plugs over the years, I only start them by hand....Or if a socket was needed , very gently any resistance and i stop and try again.......At this point, I would get a new plug Then  put the plug you think is crossed.. Aside , and carefully put the new one in...

[Grayrider]

I think I would put a drop of oil on one of the other plugs and try it in that head again - but by hand.
If you crossed threaded a plug the threads would be noticeably knarly and some bits of metal would be evident.
You should use a drop of oil on plugs when installing to ease the threads going together.

[IronButt70]

If you have the plug that came out take a file (preferably a triangle file) and file 2 small grooves across the threads 180 degrees apart. Then try screwing that plug gently in by hand. Go as far as you can by hand and the try a small amount of wrench pressure. If it stops, the threads are probably buggered. If it goes all the way in the notches will clean up the threads. Any small shavings that might be in the cylinder can be blown out by cranking the engine over with both plugs out. Done this a bunch of times on marine engines where owners have cross threaded plugs. Not always successful but can work. Helicoil is probably your only other option.

[FSG]

visit NAPA and get the appropriate size sparkplug backtap thread repair tool

[Hossamania]

visit NAPA and get the appropriate size sparkplug backtap thread repair tool

The problem is, is he going to be able to fit that in there?

[To The Max]

Pull of what ever you have to ,to get a good look at what your doing. then get the appropriate tap ( have never seen a back tap but it looks good). if you haven't done this type of work before try and get someone who has, you need to have a good feel for this job. you don't want to pull of the head. Max

[1workinman]

Ok so I think I cross threaded my front cylinder plug on my new bike. Wtf...all the other plugs went in pretty easy but were a bitch to start. The front cylinder deep one didn't want to start at all. I wiggled the plug on the end of the wrench left and right trying to get it to bite. As soon as I felt what I thought was a good bite I started gently tightening. It went in a little rough at first and then got easier but then it got tight again. I backed it out hoping it was good. The plug didn't have any metal shavings on ut but each time time I tried tightening it up it seemed to get harder.
Anyone experience this with the new m8 or did I just F $_÷\! My new motor? I cant tell if it's seated all the way but it did come to a stopping point rather quick. Like I was at the end of the threads. I pulled it out and compared the threads that looked used to one of the other plugs and they seem the same.
Any advice?

I want to chase the threads . Get the tool straight also . I know not ever one will agree but I use anti seize every time on plugs . I have used a good bolt or what ever to chase threads before if I knew the material was good material . Use a matabo to cut groves in the threads . On somethings as the head I probably want to buy a good tool to do that

[hd06]

 I pulled my plugs out to check them and I noticed how sloppy the holes were it wouldn't take too much to pull the threads, Alway put Anti-seize lube.

[klammer76]

I always use anti seize also. Steel into aluminum.

[moose]

you could always put a big gob of grease on the threads to catch any smuts that are on the threads so nothing drops into the cylinder   but still turn it over with the plug out in case any went in

[FSG]

The problem is, is he going to be able to fit that in there?

I don't know but there's only one way to find out.

It's what I'd be doing, I'd also hollow out an old plug and use it to feed low pressure air into the front cylinder while back tapping the centre plug hole

[klammer76]

visit NAPA and get the appropriate size sparkplug backtap thread repair tool

Nice tool, but my God, they are proud of it 

[Mule]

https://www.ebay.com/itm/Back-Tap-12mm-Int-Spark-Plug-Rethread-Tool-3689/230557387473?hash=item35ae4a8ad1:g:2CEAAOxybLpRf5u2

[klammer76]

https://www.ebay.com/itm/Back-Tap-12mm-Int-Spark-Plug-Rethread-Tool-3689/230557387473?hash=item35ae4a8ad1:g:2CEAAOxybLpRf5u2

I saw that when I was doing a search. Wondering if it's a cheap Chinese knock off? Have you (or anyone) tried this one?

[DTTJGlide]

The M8 plugs aren't 12mm, think they're 10mm.

[klammer76]

The M8 plugs aren't 12mm, think they're 10mm.

Thanks. The NAPA part is for two back taps, 10mm & 12mm. Cost is something like $170.00  I was looking to add a 12mm to the tool box for twin cams. Looks like a nice tool to have and I like tools but not for the NAPA price. I do wonder about the ebay item but don't know the quality of it. The price is where I feel the NAPA tool should be.

[IronButt70]

Thanks. The NAPA part is for two back taps, 10mm & 12mm. Cost is something like $170.00 

  Is it 24k gold plated?

[Hunter14]

I Have a set i bought from JC Witney back in the 70's haven't used them since then...I don't know where they were made but my point is how many times are you ever going to use them again..
All they have to do is work just one time...

[klammer76]

I Have a set i bought from JC Witney back in the 70's haven't used them since then...I don't know where they were made but my point is how many times are you ever going to use them again..
All they have to do is work just one time...

True, as long as the tool doesn't cause more problems during that one time. The ebay tool may be fine who knows? May order one to check it out.

[DanThe Man]

Been there and done this on a twinkie, 03 ultra. Biggest pos most problematic hd I ever owned. I was riding, thankfully not to far from home, and chucked a plug. Hole was stripped. It was a week before Sturgis and no one had a timesert kit in stock. Luckily I sweet talked the distributor who sent me a kit. It was the front head so i just slid the tank back and installed the sert while engine was assembled in the bike. fired right up and that particular problem never reared its head again. Dealer claimed it happened because I didn't properly torque the plugs in.

[Timber0472]

yea...the threads are jacked...no hope. had to purchase new head. I talked to a tech and he said, "yea, one time i stripped one taking it out on the new ones..wtf?" Not a lot of meat there apparently. I put it in by hand and thought it felt "ok". Guess not. By the time I realized...too late. Thanks all.